<?php

/*
 * This file is part of SwiftMailer. (c) 2004-2009 Chris Corbyn For the full copyright and license information, please view the LICENSE file that was distributed with this source code.
 */

/**
 * Analyzes characters for a specific character set.
 * 
 * @package Swift
 * @subpackage Encoder
 * @author Chris Corbyn
 * @author Xavier De Cock <xdecock@gmail.com>
 */
interface Swift_CharacterReader {
	const MAP_TYPE_INVALID = 0x01;
	const MAP_TYPE_FIXED_LEN = 0x02;
	const MAP_TYPE_POSITIONS = 0x03;
	
	/**
	 * Returns the complete charactermap
	 *
	 * @param string $string        	
	 * @param int $startOffset        	
	 * @param array $currentMap        	
	 * @param mixed $ignoredChars        	
	 * @return int
	 */
	public function getCharPositions($string, $startOffset, &$currentMap, &$ignoredChars);
	
	/**
	 * Returns mapType
	 * 
	 * @return int mapType
	 */
	public function getMapType();
	
	/**
	 * Returns an integer which specifies how many more bytes to read.
	 * A positive integer indicates the number of more bytes to fetch before invoking
	 * this method again.
	 * A value of zero means this is already a valid character.
	 * A value of -1 means this cannot possibly be a valid character.
	 * 
	 * @param int[] $bytes        	
	 * @return int
	 */
	public function validateByteSequence($bytes, $size);
	
	/**
	 * Returns the number of bytes which should be read to start each character.
	 * For fixed width character sets this should be the number of
	 * octets-per-character. For multibyte character sets this will probably be 1.
	 * 
	 * @return int
	 */
	public function getInitialByteSize();
}
